hg: jdk/sandbox: 8215624: Add parallel heap iteration for jmap ?histo

[chris.hegarty at oracle.com]

Changeset: 5036ca733469
Author:    phh
Date:      2020-08-13 11:31 -0700
URL:       https://hg.openjdk.java.net/jdk/sandbox/rev/5036ca733469

8215624: Add parallel heap iteration for jmap ?histo
Summary: Chunk and parallelize the heap scan
Reviewed-by: sspitsyn, stefank, phh

! src/hotspot/share/gc/epsilon/epsilonHeap.hpp
! src/hotspot/share/gc/g1/g1CollectedHeap.cpp
! src/hotspot/share/gc/g1/g1CollectedHeap.hpp
! src/hotspot/share/gc/parallel/parallelScavengeHeap.cpp
! src/hotspot/share/gc/parallel/parallelScavengeHeap.hpp
! src/hotspot/share/gc/serial/serialHeap.cpp
! src/hotspot/share/gc/serial/serialHeap.hpp
! src/hotspot/share/gc/shared/collectedHeap.hpp
! src/hotspot/share/gc/shared/gcVMOperations.cpp
! src/hotspot/share/gc/shared/gcVMOperations.hpp
! src/hotspot/share/gc/shenandoah/shenandoahHeap.cpp
! src/hotspot/share/gc/shenandoah/shenandoahHeap.hpp
! src/hotspot/share/gc/z/zCollectedHeap.cpp
! src/hotspot/share/gc/z/zCollectedHeap.hpp
! src/hotspot/share/gc/z/zHeap.cpp
! src/hotspot/share/gc/z/zHeap.hpp
! src/hotspot/share/memory/heapInspection.cpp
! src/hotspot/share/memory/heapInspection.hpp
! src/hotspot/share/runtime/arguments.hpp
! src/hotspot/share/services/attachListener.cpp
! src/jdk.jcmd/share/classes/sun/tools/jmap/JMap.java
! test/jdk/sun/tools/jmap/BasicJMapTest.java